Potassium bitartrate
Potassium bitartrate, also known as potassium hydrogen tartrate, with formula KC4H5O6, is the potassium acid salt of tartaric acid (a carboxylic acid)—specifically, l-( + )-tartaric acid. Especially in cooking, it is also known as cream of tartar. Tartaric acid and potassium naturally occur in grapes; its crude precipitate form, tartar or wine stone, is a byproduct of winemaking found deposited on top of must barrels, which can be purified.
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